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        <h2>
          <span class="refentrytitle">dispfft</span>
        </h2>
        <p>displayfft — 
      Displays the Fourier Transform of an audio or control signal.
    </p>
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      <div class="refsect1">
        <a id="idp99499552"></a>
        <h2>Description</h2>
        <p>
      These units will print orchestra init-values, or produce graphic display of orchestra control signals and audio signals. Uses X11 windows if enabled, else (or if <a class="link" href="CommandFlags.html#FlagsMinusLowerG"><em class="citetitle">-g</em></a> flag is set) displays are approximated in ASCII characters.
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        <a id="idp99501920"></a>
        <h2>Syntax</h2>
        <pre class="synopsis"><span class="command"><strong>dispfft</strong></span> xsig, iprd, iwsiz [, iwtyp] [, idbout] [, iwtflg] [,imin] [,imax]</pre>
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      <div class="refsect1">
        <a id="idp99503984"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>iprd</em></span> -- the period of display in seconds.
    </p>
        <p>
      <span class="emphasis"><em>iwsiz</em></span> -- size of the input window in samples. A window of <span class="emphasis"><em>iwsiz</em></span> points will produce a Fourier transform of <span class="emphasis"><em>iwsiz</em></span>/2 points, spread linearly in frequency from 0 to sr/2. <span class="emphasis"><em>iwsiz</em></span> must be a power of 2, with a minimum of 16 and a maximum of 4096. The windows are permitted to overlap.
    </p>
        <p>
      <span class="emphasis"><em>iwtyp</em></span> (optional, default=0) -- window type. 0 = rectangular, 1 = Hanning. The default value is 0 (rectangular).
    </p>
        <p>
      <span class="emphasis"><em>idbout</em></span> (optional, default=0) -- units of output for the Fourier coefficients. 0 = magnitude, 1 = decibels. The default is 0 (magnitude).
    </p>
        <p>
      <span class="emphasis"><em>iwtflg</em></span> (optional, default=0) -- wait flag. If non-zero, each display is held until released by the user. The default value is 0 (no wait).
    </p>
        <p>
      <span class="emphasis"><em>imin</em></span> (optional, default=0) -- minimum FFT bin used in display.
       </p>
        <p>
      <span class="emphasis"><em>imax</em></span> (optional, default=winsize/2) -- maximum FFT bin to be used in display.
    </p>
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      <div class="refsect1">
        <a id="idp99512640"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>dispfft</em></span> -- displays the Fourier Transform of an audio or control signal (<span class="emphasis"><em>asig</em></span> or <span class="emphasis"><em>ksig</em></span>) every <span class="emphasis"><em>iprd</em></span> seconds using the Fast Fourier Transform method.
    </p>
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      <div class="refsect1">
        <a id="idp99515696"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the dispfft opcode. It uses the file <a class="ulink" href="examples/dispfft.csd" target="_top"><em class="citetitle">dispfft.csd</em></a>.
      </p>
        <div class="example">
          <a id="idp99517552"></a>
          <p class="title">
            <strong>Example 197. Example of the dispfft opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac     <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if realtime audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o dispfft.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">nchnls</span> <span class="op">=</span> 2
<span class="ohdr">0dbfs</span> <span class="op">=</span> 1

<span class="oblock">instr</span> 1

kcps <span class="op">=</span> 110
ifn  <span class="op">=</span> 1

knh	<span class="opc">line</span> p4, p3, p5
asig	<span class="opc">buzz</span> 1, kcps, knh, ifn
	<span class="opc">outs</span> asig, asig

<span class="opc">dispfft</span>	asig, .1, 2048, 0, 1

<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="comment">;sine wave.</span>
<span class="stamnt">f</span> 1 0 16384 10 1

<span class="stamnt">i</span> 1 0 3 20 20
<span class="stamnt">i</span> 1 + 3 3 3
<span class="stamnt">i</span> 1 + 3 150 1
<span class="stamnt">e</span>

<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
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        <p><br class="example-break" />
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        <h2>See Also</h2>
        <p>
      <a class="link" href="display.html" title="display"><em class="citetitle">display</em></a>,
      <a class="link" href="print.html" title="print"><em class="citetitle">print</em></a>
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